(define ans 0)
(define l (read))
(define n (read))
(define w (list))
(let loop((i n))
	(set! w (cons (read) w))
	(if (> i 1) (loop (- i 1))))
(sort w)
(define (solve ls)
	(if (> l (car ls))
		(set! ans (+ ans 1)))
	(if (> l (car ls))
		(set! l (- l (car ls))))
	(if (> l (car ls))
		(solve (cdr ls))))
(solve w)
(display ans)
(newline)